I would like to confirm the handling of this scenario.

A client who is a resident of NJ, but works in PA gave me his W-2.

The wages in box 1 is $30,000.

NJ state wages is $30,000.

PA state wages is $30,000.

Is he taxed on all $30,000 of wages on his PA non-resident tax return, and the same $30,000 wages as a NJ resident?  I understand there is a tax credit for wages taxed in another state on his NJ tax return.  Anything else I should be considering?

Thank you!